Compound change gear transmissions of the type having one or more auxiliary sections connected in series with a main transmission section are known in the prior art. Auxiliary transmission sections are of three general types: range, splitter, or combined range/splitter.
Examples of compound transmissions having range type auxiliary sections may be seen by reference to U.S. Pat. No. 3,105,395; U.S. Pat. No. 2,637,222; and U.S. Pat. No. 2,637,221, the disclosures of which are hereby incorporated by reference. Examples of compound change gear transmissions having splitter type auxiliary sections may be seen by reference to U.S. Pat. No. 4,290,515; U.S. Pat. No. 3,799,002; U.S. Pat. No. 4,440,037; and U.S. Pat. No. 4,527,447, the disclosures of which are hereby incorporated by reference. Examples of a compound transmission having a single combined range/splitter type auxiliary section may be seen by reference to U.S. Pat. No. 3,283,613 and U.S. Pat. No. 3,648,546, the disclosures of which are hereby incorporated by reference.
Blocked change gear transmissions of both the single and the compound types are also well known in the prior art as may be seen by reference to U.S. Pat. No. 3,799,002; U.S. Pat. No. 3,921,469; U.S. Pat. No. 3,924,484; U.S. Pat. No. 3,983,979; U.S. Pat. No. 4,192,196; and U.S. Pat. No. 4,194,410, all of which are hereby incorporated by reference.
It should be noted that the terms main and auxiliary section are relative and that if the designations of the main and auxiliary sections are reversed, the type of auxiliary section (either range or splitter) will also be reversed. In other words, given what is conventionally considered a four-speed main section with two-speed range type auxiliary section, if the normally designated auxiliary is considered the main section, the normally designated main section would be considered a four-speed splitter type auxiliary section therefor. By generally accepted transmission industry convention, and as used in this description of the invention, the main transmission section of a compound transmission is that section which contains the largest (or at least no less) number of forward speed ratios, which allows selection of a neutral position, which contains the reverse ratio(s) and/or which is shifted (in manual or semiautomatic transmissions) by manipulation of a shift bar or shift rail or shift shaft/shift finger assembly as opposed to master/slave valve/cylinder arrangements or the like.